Geometer Sketchpad is far from a new innovation, but its potential in the classroom is probably still understated. The application described here can be replicated in any classroom, and the impact on learning is likely to be significant. The experiences documented are "real", and show how a software package can enhance an area of the mathematics…

The ability of interlocking polygonal tiles, like those in the "Polydron Frameworks kit," to flex can give rise to polyhedra whose faces don't quite fit. In this article, the author discusses what happens with polyhedra whose faces don't quite fit. (Contains 2 notes.)